What does supporting Thunderbird have to do with it. Their own server generated the error. Are they not smart enough to troubleshoot their own error messages?

No, I don't think they are smart enough to troubleshoot their own error messages. I called on Monday, and the guy on the help desk was useless - asking me to check the incoming pop server for a problem with outgoing messages.

The last one at least acknowledged that my e-mail program was immaterial until the server error was identified. Unfortunately she had no idea how to do that, and actually used google to figure out (in general terms) what it meant. And she was the GOOD one

These temporary server errors are usually a problem at the server end, but I have seen issue where they do that when things like passwords are not used as well.

Please add the Mail and News Accounts from troubleshooting information to your post To find the Troubleshooting information:

• Open Help (or click on three-line-icon and select Help)
• Choose Troubleshooting Information
• Use the button Copy to clipboard to select all. Do not check box "Include account names"!
• Paste this in your post.

Looking at the bell web site. They really know how to sound caring and offer no real information. I can locate information that indicates that they are doing some sort of email migration starting in 2016. They also suggest new email settings. http://support.bell.ca/Internet/Email/Manually-update-Bell-mail-program-settings

Notably there does not appear to be a pop option which was all they offered in the past. Most providers simply offer both. I have no idea if this migration includes you at this time. Bu I would guess that yes it does. I would also guess they contacted you the best part of a year ago and your did not understand the communication and ignored it, possibly thinking it was some sort of marketing mail to sell you something.

But I think perhaps you might contact bell about if you have been upgraded. Perhaps they are capable of answering that question. In the meantime please post those account settings and we will see what we can learn about them working or not.

@Matt: Thank you for your very in-depth reply.

Actually, I did do the e-mail migration a year ago - even then they told me that they didn't support Firebird, but I could still use it. It was just up to me to go through the various instructions for Outlook and figure out the SMTP and POP servers on my own, as well as the various ports. It wasn't until a week and a half ago that I started having this problem, and the Mozilla Release Notes page says that the last update was on December 28th, more than two weeks before my problem occurred.

When I talked to the one help desk member who was actually helpful, she suggested that the port number I was using might be the problem. She gave me some alternate ports, and they didn't work. I need to go through last years update again and double check the numbers.

The problem shouldn't be the passwords - I haven't changed them for at least 6 months, and they work on the webmail just fine.

Thank you for the instructions on how to get to the troubleshooting information - I will try that as well.

Once again, thank you for your help. Your broad ranging answered ensured that there would be some things that I hadn't tried yet.

Account settings will be my next post.

David T. Shaw

Email providers configure their servers. There is no excuse for them not to know what server settings work for them.

Here are my settings for my Outgoing Server (SMTP):

Description: smtphm.sympatico.ca Server Name: Bell Port: 25 (originally at 465 before calling help desk) User Name: <not specified> Authentication method: Normal password Connection Security: STARTTLS (originally STL/TLS before calling help desk)

While looking at the settings, I noticed that under the Account name, at the bottom there is a spot for Outgoing Server (SMTP):. It was set in all three of my e-mails as "Microsoft Live Hotmail - smtp-mail.outlook.com" I decided to change it to the smtphm.sympatico.ca server, and I now get the message: Sending of the message failed. An error occurred while sending mail: Outgoing server (SMTP) Bell is unknown. The server may be incorrectly configured. Please verify that your Outgoing server (SMTP) settings are correct and try again.

I am going to switch the configuration on the server I was using to the server I should be using and see what happens.

Port 25 is normally an insecure port and its use has been discontinued by most reputable providers for security concerns. I would expect to see connection security set to None and not STARTTLS of SSL/TLS when using an insecure port.

The other common, and secure, ports are 465 and 587 and they will use one of the 2 connection security protocols.

Insecure ports like 25 generally do not work if you are trying to send mail outside of the providers own network.

Good reading. Scroll down to Today's Usage for port descriptions. http://blog.mailgun.com/25-465-587-what-port-should-i-use/

Well, that didn't work. At least I've learned that editing the SMTP at the bottom of the 'options' menu is not the same as setting the SMTP server.

Going back to read Bell's switch over settings again.

The problem is solved.

All I had to do was add a new server with the settings on the Bell webpage. I don't know why Thunderbird couldn't find my old default - there may have been a mistake that I couldn't see. I don't know why my outgoing STMP changed to an older version (the error messages I was receiving weren't even from Bell but from smtp-mail.outlook.com

Airmail, thanks for the link. I have to read the article and then ask Bell why their default link is an insecure one.

Thanks all for the help.